need reference on where the transmission should sit in relation to the firewall

I'm finally working full speed ahead on the Mirada. Got the 727 transmission roughed into place, but now I'm second guessing myself because I don't want to do this twice... thing is heavy especially since I'm working alone!

I'm using a custom tubular trans crossbrace (with a stock mount), hence, I cannot just reference a manual or photos for how it goes. However, I think I have it in the orientation it's intended.

So the question: Where should the front of the trans housing sit in relation to the firewall? Slightly in front of it, level, or a little behind it, actually a little into the tunnel? Right now, it's slightly in FRONT of the firewall and if I measure for the length of the engine, it doesn't look like a fan will fit with the radiator, so I don't think that's right. If I put it back any farther, it seems like it might be hard to get the transmission-to-engine bolts in (but I can figure that out if need be).

And I can't measure the driveshaft, because I don't have one yet, will have to get a custom one made once the rest of the drivetrain is in.

So... anyone got any advice or photos or measurements? I can post a pic of what I have if that would help.
Author: 72Dodge